Overhead lockers with a lowerable shell are currently used in passenger aeroplanes in particular as they advantageously allow optimum use of space and, at the same time, a high degree of operating convenience. The lowerable shell is pivotal from an upper closed position, in which optimum head freedom of the passenger sitting under the overhead lockers is ensured, into a lower, open loading or unloading position. Even relatively short people can comfortably deposit or remove items of luggage in/from the shell in the loading or unloading position.
Overhead lockers of this type conventionally comprise a retention system which is used to pivotally fasten the lowerable shell on a component secured to the structure, such as an overhead locker housing and/or a ceiling construction of an aircraft passenger cabin. The retention system may, moreover, be used to introduce tensile forces of a force-assisting device to raise the lowerable shell. A typical retention system comprises a cable, optionally guided over one or more guide roller(s), the ends of which are connected to the lowerable shell or the component secured to the structure.
A closure mechanism is also conventionally provided which can be provided in an easily accessible position and can be easily actuated. In its closed position the closure mechanism holds the lowerable shell in its upper closed position, while in its open position it allows lowering of the overhead locker shell from its upper closed position into its lower, open loading or unloading position. Consequently convenient operation of the overhead locker is made possible. At the same time risks of injury are avoided which, for example, could result owing to uncontrolled lowering of the shell.
In principle, for safety reasons, there is a need in particular when using an overhead locker with a lowerable shell in passenger aeroplanes that the lowerable shell can be brought from its upper closed position into its lower, open loading or unloading position even in the event of the retention system malfunctioning, which can be triggered for example by jamming of the cable or a fire in the overhead locker. Therefore overhead lockers of this type also comprise an emergency opening device which, if required, separates the retention system from the lowerable shell or component secured to the structure. For example the emergency opening device may be configured in such a way that it separates the guided cable of the retention system from the lowerable shell in the event of an actuation.
A known emergency opening device comprises a shearing pin which tears when a corresponding trigger force is applied, for example by forceful pulling on the lowerable shell, so that the guided cable of the retention system is separated from the lowerable shell. Use of an emergency opening device with a shearing pin has the drawback that, depending on the overall construction of the overhead locker and the lever conditions resulting therefrom on the guided cable of the retention system, very high forces are possibly required to trigger the emergency opening device. Owing to manufacturing and assembly tolerances high dispersion of the triggering force may also occur. It is also disadvantageous, in particular in the event of a fire in the overhead locker, that the emergency opening device has to be actuated by pulling on the lowerable shell as smoke or flames may possibly issue from the overhead locker and injure the person actuating the emergency opening device. Finally, during normal operation of the overhead locker there is the risk of unintentional triggering of the emergency opening device.
DE 100 01 038 A1 discloses an overhead locker with a lowerable shell which comprises a motive drive device for lowering the overhead locker shell from an upper closed position into a lower, open position and for raising the overhead locker shell from the lower, open position into the upper closed position. The drive device is, for example, constructed as a toothed belt drive and comprises a drive motor, the rotary movement of which can be transmitted via a splined shaft to a toothed belt. A catch of the toothed belt drive is fastened to support arms of the lowerable shell via brackets provided with rollers, so that the lowerable shell can be moved between its upper closed position and its lower, open position by an actuation of the toothed belt drive. To fix the overhead locker shell in its upper closed position there is a locking device driven by a lifting magnet which can be actuated by means of an actuating switch. To allow manual opening and closing of the overhead locker even in the event of failure of the motive drive device, a coupling arranged on the splined shaft of the toothed belt is provided. The coupling can be moved via a hand lever and a cable pull into a disengaged position in order to decouple the non-functioning drive motor from the force-transmitting components of the belt drive. Actuation of the actuating switch can subsequently unlock the lifting magnet-operated locking device and the overhead locker shell can be manually moved into its lower, open position.
The object of the invention is to provide an emergency opening device for an overhead locker with a lowerable shell, which device, if required, allows reliable separation of a retention system for fastening the lowerable shell to a component secured to the structure from the lowerable shell or the component secured to the structure and which can also be actuated simply and safely. The invention is also directed to the object to providing an overhead locker fitted with an emergency opening device of this type.